This disclosure relates to a turbine engine seal that is used to seal a combustor relative to a turbine nozzle.
Turbo machines or engines, such as auxiliary power units, have two typical configurations for turbines. An axial turbine engine generally provides an axial flow path through the turbine. Compressed fluid exiting the combustor flows in a generally axial path through the turbine. In a radial turbine engine, the compressed fluid exits the combustor and enters the turbine radially. Each turbo machine presents unique challenges to sealing the combustor relative to a turbine nozzle.
Some axial turbine engines include a combustor sealing arrangement having a floating ring seal. One end of the floating ring seal is received in a radially oriented U-shaped structure provided by the combustor for permitting the floating ring seal to slide radially relative to a combustor liner. An opposite end of the floating ring seal provides a seal against an outer diameter of an outer wall of the turbine nozzle. No other structure on the combustor is used to seal against the outer wall.
A “birds mouth” seal has been used in some radial turbine engines to seal the combustor relative to the turbine nozzle. A portion of the combustor liner is arranged on one side of a nozzle wall, and a seal, which is secured to the combustor liner by a braze, is arranged on the other side of the nozzle wall. As the combustor vibrates and expands during operation, the brazed joint or the liner can crack. What is needed is a more robust seal for a radial turbine engine.